(1) Field of the Invention
The present invention relates to a method and an apparatus for estimating the quality of grains, and more particularly to a method and an apparatus with which the quality of the grains after the harvesting can be estimated during the growth of the grain plant prior to the harvesting.
(2) Description of the Related Art
In respect of the rice, it is already known to estimate the amount of protein content in the final brown rice from the biological data obtained before the harvesting period. For example, there has been a disclosure wherein the protein content rate of the brown rice is estimated from the leaf blade nitrogen content rate at the full heading time (disclosed in Ninth non-destructive measurement symposium, November 1993, by Kansai Branch of Nihon Food Product Industry Association; and in Nutrition diagnosis of rice plant by near infrared ray spectral of a fresh leaf, by Keisuke Yoshimatsu, Agricultural Product Processing Study of Yamaguchi Agricultural Experimental Laboratory). However, according to the disclosed technique; the leaf blade was chemically analyzed for preparing an estimation formula, and it was inevitable to consume the time for the preparation of the estimation formula. Also, when the correlation between the leaf blade from the stalk of the given rice plant and the brown rice harvested from the same is observed, since the leaf blade had to be cut from the stalk and used for the chemical analysis, and since the brown rice had to be harvested from the rice plant from which the leaf blade used for the chemical analysis was missing after the chemical analysis, it could not be denied that there would be a shortage in the component or composition produced by the photosynthesis. To prepare the estimation formula from the leaf blade nitrogen content rate and the amount of the harvested brown rice obtained as above will become a cause for lowering the precision.
For estimating the protein content rate in the wheat grains, there is a disclosed example for estimating the protein content rate in the matured grains based on the protein content rate in the immatured grains 30 days before the harvesting (The journal of agriculture, Victoria, May 1963). The disclosure relates to a method of estimating the protein content rate by chemical analysis of the matured particle based on the protein content rate by chemical analysis of the immatured particle. This method requires time for preparing the estimation formula and, since the stalk of the same wheat as that used for the immatured particle is taken and used for the analysis of the matured particle, a shortage in the component or composition is caused and this becomes a cause for the lowering of the precision for the same reason as for the rice plant as explained above. Also, in the case of wheat, since the plant grows in a dried field, there does not exist, unlike with the rice plant which grows in a paddy field, a damper mechanism in which the weather and the fertilization are standardized by water. For this reason, the wheat plant is under the conditions in which the weather conditions such as the duration of sunshine and the accumulated temperature directly affect through the soil so that, even when a biological data for a certain one period before the harvesting is obtained, there is a possibility that the growth estimation curve changes drastically by the subsequent environmental changes. Therefore, as compared with rice, it is extremely difficult to estimate the protein content amount of the matured wheat particle.